Patent attributes
A method comprising: A) using a mobile device's camera to capture a first image; B) by reference to a first illumination source appearing in the first image, determining first heading information of the mobile device; C) as the mobile device moves to a second location, using one or more inertial sensors of the mobile device to extrapolate a plurality of extrapolated first candidate locations and respective first candidate headings of the mobile device; D) at the second location, using the camera to capture a second image; E) by reference to a second illumination source appearing in the second captured image, determining a plurality of second candidate locations and respective second candidate headings of the mobile device; and F) based on a comparison of the extrapolated first candidate locations and headings with the second candidate locations and headings, determining at least one estimated location and respective heading of the mobile device.